Kevin Vallely remembers well when he first felt the call of the Arctic. As a child growing up in Montreal, the architect and adventurer’s father would regale him with stories of working as a radio operator in northern Labrador.

“It was just a brutal, harsh place, yet strangely enticing and magnificent as well,” says Vallely. “He talked about how lonely, and quiet, and desolate it was. It intrigued me: this place that is part of our country, yet so completely out there and inhospitable. It just painted a scene of something so adventurous and unique.”

He would get his first experience with the Far North in 2000, strapping on a pair of skis to traverse Alaska’s Iditarod Trail. Competing in the first ever Iditasport Impossible — described by Nerve Rush as “the Ironman’s badass uncle who did a tour in Vietnam and went back for vacation” — Vallely and his companions travelled over 1,000 frozen miles from Knik to Nome.

“I had no idea what I was getting myself into at all,” he laughs. “I mean, the banner across the start line — their motto for this race was ‘Where cowards won’t show and the weak will die.’”

Vallely completed the race, and three years later, he was back: this time, riding a bicycle from Dawson City, Yukon to Nome, Alaska. Over the ensuing years, the Vancouver-based adventurer would embark on over a dozen expeditions around the world, becoming a World Record-holder for his trek to the South Pole and earning the title of one of Canada’s leading adventurers by the Globe and Mail.

Still, one elusive ‘first’ remained: traversing the Northwest Passage under human power. Vallely had first entertained thoughts of the crossing twenty years ago, while swapping stories with a friend.

“Traversing the Northwest Passage solely under human power in a single season was something that no-one had ever even come close to achieving,” says Vallely. “At the time, we both laughed and said it’s impossible.”

The melting sea ice gave him an opening, and a purpose: If Vallely and his fellow expeditioners could row the Northwest Passage unimpeded, perhaps they could draw attention to the urgency of global warming. Along with three other adventurers — two Irishmen and a fellow Canadian — Vallely set off in 2013 in a custom ocean rowing boat, intent on completing the crossing in a single season. The story has become Vallely’s first book, Rowing the Northwest Passage: Adventure, Fear, and Awe in a Rising Sea.

“It’s the classic canary in the coalmine. The Arctic is melting twice as fast as anywhere on Earth,” says Vallely. “I don’t think we realize how profoundly [things] will change … We need to do something about it.”